问题
My Java programm produces a lot of data, with wich I construct individual ResultObject. Because only certain ResultsObjects will be of interest, I populate an ObservableHashMap<> with my results. The CustomObject consists of a handful ints + doubles and one JSONObject. With this CustomObject I want to map similar ResultObjects(which have certain properties in common) to that one CustomObject.
While mapping and handling those results works as intended, I am pretty much helpless to populate a TableView with that ObservableHashMap<>.
My CustomObject (JSONObject simply to check, if two CustomObjects have the same properties):
public CustomObject(Simulation data) {
this.datapoint1 = data.datapoint1;
this.datapoint2 = data.datapoint2;
this.jsonCompareObject = new JSONObject()
.put("datapoint1", data.datapoint1)
.put("datapoint1", data.datapoint2);
}
My ObservableHashMap Object:
private ObservableMap <CustomObject, ObservableList<Simulation>> topResultsList;
public SomeObjectWithObservableMap(){
this.topResultsList = FXCollections.observableHashMap();
}
By using the following code, I check if there is a key with the corresponding datapoints already present to then add to its ObservableList (Value):
private boolean isKeyPresent(CustomObject newCustomObject, Simulation data) {
for (CustomObject oldCustomObject : this.topResultsList.keySet()) {
if (oldCustomObject.jsonCompareObject.toString().equals(newCustomObject.jsonCompareObject.toString())) {
this.topResultsList.get(oldCustomObject).add(data);
return true;
}
}
return false;
}
I populate some other TableView like this:
{
tableColumn.setCellValueFactory(new PropertyValueFactory<>("datapoint1"));
tableColumn.setCellFactory(TextFieldTableCell.<SomeObject, Double>forTableColumn(twoDigits));
tableView.setItems(someObject.getObservableList());
}
In the end I want some TableColumns to show properties from the CustomObject. Later on, I would want the individual mapped ObservableLists of a selected CustomObject to be shown in a seperate TableView.
I am pretty new to Java and JavaFX and I hope to have described my problem as professional as possible. Please let me know, if I missed anything.
回答1:
This should work for a List<Map<String,String>>
Main.java
package tester;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.scene.Scene;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.layout.HBox;
import javafx.stage.Stage;
public class Tester extends Application
{
@Override
public void start(Stage primaryStage)
{
TableView<LineItem> table = new TableView<>();
List<Map<String, String>> databaseObject = getDatabaseObject();
for (String key : databaseObject.get(0).keySet())
{
TableColumn<LineItem, String> col = new TableColumn<>(key);
col.setCellValueFactory((TableColumn.CellDataFeatures<LineItem, String> cellData) -> cellData.getValue().fieldProperty(key));
table.getColumns().add(col);
}
List<LineItem> data = new ArrayList<>();
LineItem sequence1 = new LineItem(databaseObject.get(0));
LineItem sequence2 = new LineItem(databaseObject.get(1));
data.add(sequence1);
data.add(sequence2);
table.setItems(FXCollections.observableArrayList(data));
table.setPrefWidth(500);
HBox root = new HBox();
root.getChildren().addAll(table);
Scene scene = new Scene(root, 500, 500);
primaryStage.setTitle("Hello World!");
primaryStage.setScene(scene);
primaryStage.show();
}
/**
* @param args the command line arguments
*/
public static void main(String[] args)
{
launch(args);
}
private List<Map<String, String>> getDatabaseObject()
{
List<Map<String, String>> values = new ArrayList<>();
Map<String, String> record1 = new HashMap<>();
record1.put("firstName", "Joe");
record1.put("lastName", "Blob");
record1.put("address", "95 circle ave");
record1.put("city", "Toronto");
record1.put("postalCode", "L9Y4Z4");
values.add(record1);
Map<String, String> record2 = new HashMap<>();
record2.put("firstName", "Sarah");
record2.put("lastName", "Blob");
record2.put("address", "92 main st");
record2.put("city", "London");
record2.put("postalCode", "T9Y4K4");
values.add(record2);
return values;
}
}
LineItem.java
package tester;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
public class LineItem
{
private final Map<String, StringProperty> fields;
public LineItem(Map<String, String> record)
{
this.fields = new HashMap<>();
for (String key : record.keySet())
{
this.fields.put(key, new SimpleStringProperty());
}
for (Entry<String, String> entry : ((Set<Entry<String, String>>) record.entrySet()))
{
this.fields.get(entry.getKey()).set(entry.getValue());
}
}
public final StringProperty fieldProperty(String key)
{
return this.fields.get(key);
}
}
回答2:
The other way to create a TableView with one Map<String,String> is:
Main.java
package tester;
import java.util.HashMap;
import java.util.Map;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.TableView;
import javafx.scene.layout.HBox;
import javafx.stage.Stage;
public class Tester extends Application
{
@Override
public void start(Stage primaryStage)
{
MapTable mapTable = new MapTable(getDatabaseRecord());
TableView table = mapTable.getTableView();
HBox root = new HBox();
root.getChildren().addAll(table);
Scene scene = new Scene(root, 500, 500);
primaryStage.setTitle("Hello World!");
primaryStage.setScene(scene);
primaryStage.show();
}
/**
* @param args the command line arguments
*/
public static void main(String[] args)
{
launch(args);
}
private Map<String, String> getDatabaseRecord()
{
Map<String, String> record1 = new HashMap<>();
record1.put("firstName", "Joe");
record1.put("lastName", "Blob");
record1.put("address", "95 circle ave");
record1.put("city", "Toronto");
record1.put("postalCode", "L9Y4Z4");
return record1;
}
}
MapTable.java
package tester;
import java.util.Map;
import javafx.beans.property.SimpleStringProperty;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.control.SelectionMode;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
public class MapTable
{
private final TableView<Map.Entry<String, String>> table;
private final ObservableList<Map.Entry<String, String>> data;
public MapTable(Map map)
{
this.table = new TableView<>();
this.data = FXCollections.observableArrayList(map.entrySet());
setUpTable();
}
private void setUpTable()
{
this.table.setEditable(false);
this.table.setItems(this.data);
this.table.getSelectionModel().setSelectionMode(SelectionMode.MULTIPLE);
// use fully detailed type for Map.Entry<String, String>
TableColumn<Map.Entry<String, String>, String> column1 = new TableColumn<Map.Entry<String, String>, String>();
column1.setMinWidth(125);
column1.setSortable(false);
column1.setCellValueFactory((TableColumn.CellDataFeatures<Map.Entry<String, String>, String> p) -> new SimpleStringProperty(p.getValue().getKey()));
TableColumn<Map.Entry<String, String>, String> column2 = new TableColumn<Map.Entry<String, String>, String>();
column2.setMinWidth(350);
column2.setSortable(false);
column2.setCellValueFactory((TableColumn.CellDataFeatures<Map.Entry<String, String>, String> p) -> new SimpleStringProperty(p.getValue().getValue()));
this.table.getColumns().setAll(column1, column2);
}
public TableView getTableView()
{
return this.table;
}
}
来源：https://stackoverflow.com/questions/55795528/how-to-fill-tableview-with-observablemapkeyobject-observablelistcustomobject